In the mobile communications technologies, limited spectrum resources are a major factor hindering improvement of system performance. As mobile users grow rapidly and new services call for efficient data transmission, how to effectively improve spectrum efficiency has become a hot topic of research in the industry.
In the prior art, a carrier aggregation technology is one of methods for effectively improving spectrum efficiency. The carrier aggregation technology means that a service is provided to user equipment (English: User Equipment, UE for short) by simultaneously using multiple component carriers. In the multiple component carriers that simultaneously provide the service for the UE, generally, one component carrier is a primary component carrier, and the other component carriers are secondary component carriers.
There are at least the following problems in the prior art. In the carrier aggregation technology, there are only two roles: primary component carriers and secondary component carriers, and no further roles are assigned to secondary component carriers. Actually, these secondary component carriers also vary in importance according to their different bearer functions. For example, a secondary component carrier with a better bearer function has a higher degree of importance than a secondary component carrier with a worse bearer function. In this case, dividing the multiple component carriers into the primary and secondary component carriers only is not conducive to management of an important secondary component carrier.